Walmart executives have reason to cheer, while many neighborhood businesses take time to mourn. And at City Hall, that rustling sound is developers filing plans to get in on the last burst of building in the transformational tenure of Mayor Thomas M. Menino.

The mayor’s exit after two decades in office will have a profound impact on the local economy — and on business executives who over the years were defined as either an enemy of Menino or, more often, a friend. In a city where everyone in the business community knew where they stood, suddenly no one is quite sure what happens next.

“Change is going to create a lot of uncertainty,” said Richard Dimino, executive director of the business group A Better City. “The next mayor is is going to have to bring clarity quickly, so we don’t lose any momentum.”

Momentum is something the city now has in abundance. Under Menino, Boston has been reborn, from its neighborhood streets to the peaks of its skyline. Businesses are growing again in the wake of the recession, revitalizing commercial districts Menino has labored to rebuild since his earliest days as a city councilor in the mid-1980s.

As mayor, he has been obsessed with development. Scarcely has a brick been laid without Menino’s approval or a new cafe opened without him meeting its owner. His vision for Boston has created a bustling, younger city with towering buildings in select locations downtown, and green space and intimate shopping streets from Roslindale to Jamaica Plain to East Boston.

David L. Ryan/Globe Staff/File

Development along the South Boston Waterfront includes construction of the Boston Wharf Tower on A Street.

Because of the ferocity of his opinions — and the consequences of opposing them — it became a basic requirement of doing business in Boston to know Menino’s position about any project before proposing it publicly.

“He has a very strong mind, and he can be a charming guy, but you want to stay on that charming side,” said Charles Euchner, a former employee of the Boston Redevelopment Authority who left in 2000. “He became so powerful that people were reluctant to present him with new ideas out of fear he wouldn’t like them. There was almost a preediting process.”

At times, Menino’s policies drew harsh criticism from development opponents or the rare business owner who dared challenge him publicly. Critics have accused him of giving up too much to developers, particularly friends and campaign contributors.

But Menino also got plenty for everyday citizens in return. To book-smart executives, his rough-hewn manner and unpolished speech made him seem easy to outwit — until they found themselves outflanked and outworked by a surprisingly deft strategist.

Gifford said Menino often used his personal touch and humor to build relationships with local leaders, getting them to support pet causes or key events such as the 2004 Democratic National Convention. Many learned they ignored his wishes at their own peril.

“When you crossed swords with the mayor, you needed a good suit of armor,” Gifford said.

While Menino became a practiced hand at staging glitzy events and pushing the skyline to new heights, his impact on small business owners in the city’s neighborhoods was perhaps as significant. Most notably, he opposed Walmart bringing a grocery store to Dudley Square out of fear it would hurt a local food store.

Gregory Laham, owner of Sullivan’s Pharmacy in Roslindale, first met Menino as a city councilor in 1984, when he pitched a plan for business owners to revitalize Roslindale Square.

“We all thought, ‘How much is this going to cost us?’ ” said Laham, now a close friend of Menino’s. “Roslindale was not a good area. There was arson and a lot of drugs. But he was very forceful, and he knew how to organize and make it work. He absolutely changed Roslindale.”

Many developers and business owners recalled Menino’s tough determination to get big things done.

“He is a rockhead when it comes to doing something he knows is going to make the city a better place,” said Joseph Fallon, a developer who has worked closely with Menino to redevelop much of the South Boston Waterfront. “He wanted to change the waterfront to create jobs and make it a better environment. And he held that in his mind until it finally happened.”

Fallon is now building two towers for Vertex Pharmaceuticals Inc. at Fan Pier, one of the largest privately funded development projects in the country. Vertex’s decision to move to the waterfront from Cambridge grew out of personal talks between Menino and top Vertex executives.

David L. Ryan/Globe Staff/File

Mayor Menino, along with state and US highway officials, celebrated a major completion of the Big Dig in 2003.

“The mayor has this very clear vision of building this new community down at the seaport,” said Vertex chief executive Jeffrey Leiden. “He didn’t talk about the seaport as a business center, he talked about it as a neighborhood.”

The seaport is perhaps the clearest — and largest — place where Menino’s legacy will be visible for decades to come. He renamed the area the Innovation District and then set out on a sales mission to lure the kind of cutting-edge technology companies he believed would propel Boston’s economy for another generation.

Among those buying the pitch was MassChallenge, a successful competition for start-ups that in 2009 was trying to decide between Cambridge and Boston for a new home.

“He just said, ‘You know, John, if you go to Cambridge, you’ll just be one in a thousand. Come to Boston, and you’ll be special,’ ” said MassChallenge chief executive John Harthorne.

While Menino’s policies have modernized Boston and shaken off some of its parochial ways, some in the business community said he could have gone farther.

Greg Selkoe, chief executive of the online fashion retailer Karmaloop, drew Menino’s ire when he and others unsuccessfully pushed the mayor to extend the city’s nightlife past 2 a.m. After he and others posted an Internet video poking fun at the mayor, they were branded by City Hall as “antagonistic”

“He’s a very sensitive person. He feels it’s disloyal to disagree with him,” said Selkoe, who once worked for the city. “You are either with him or against him. He used a type of leadership style that was very top down, a very autocratic style.”

But Menino’s singlemindedness has also led to dramatic breakthroughs. He oversaw the city during one of its most disruptive periods — the Big Dig — which clogged downtown with traffic and construction. Menino vowed to keep businesses open and accessible, even during the constant rattle of heavy construction.

“He was an incredibly steady hand,” said Dimino. “If something needed to get done to keep traffic moving or take care of a neighborhood problem, he would make a phone call. He did it quietly, but he was a strong advocate for Boston during that period.”

The project ultimately yielded the Rose Fitzgerald Kennedy Greenway parks in place of the old highway, opening the downtown to a period of rapid redevelopment. A dozen residential and office towers are now rising on the waterfront and in the city’s core neighborhoods.

Boston’s vibrancy has also begun to fan out to places it hadn’t touched in decades, such as East Boston and Roxbury.

Darnell Williams, president of the Urban League of Eastern Massachusetts, credits the mayor with jump-starting Dudley Square in Roxbury with a string of projects, including the renovation of the old Ferdinand furniture store into the School Department headquarters, a new district police station, and the impending redevelopment along Melnea Cass Boulevard.

“All of these are very much vitally connected to the mayor’s vision of turning around the image of Roxbury as a wasteland of disinvestment to one of reinvestment,’’ Williams said.

Menino’s successor, Williams said, has enormous shoes to fill. For starters, any new mayor will need to have a firm grasp of the neighborhoods, municipal finance, and labor contracts, he noted.

“That job is not for the faint-hearted,’’ said Williams.

Laham, the Roslindale pharmacy owner, said a big heart and a grasp of the city’s neighborhoods were Menino’s most endearing traits. He recalled the mayor showing up at his pharmacy one day a couple years ago and proposing to go for a ride in the city. “He said he had some time between events, so we just drove around for a couple of hours,” Laham said. “Pretty soon he had a notebook out and he started taking notes on every pothole, every crack in the sidewalk or broken street light. It was incredible. He paid attention to everything. And the great thing was that he really cared about those issues and always followed through to fix them.”

Todd Wallack, Michael B. Farrell, Robert Weisman, and Beth Healy of the Globe staff contributed to this report. Casey Ross can be reached at cross@globe.com.